Harrison is expected to throw off flat ground for at least another four weeks before he begins throwing off a mound. He has been sidelined since April 6 with a back injury and is hopeful of returning at some point in mid-August.
Oswalt, who signed with the Rockies in May, made five starts at Double-A Tulsa, posting a 2.16 ERA and 0.93 WHIP in 33 1/3 innings of work. This will be his first start since Sept. 9 for the Rangers.
Hammel has been pushed back due to a stomach illness. He was originally expected to pitch Monday against Detroit and has already been pushed back twice. Gonzalez left the team late Monday night to go on paternity leave.
Lewis threw off a mound Monday for the first time since he was shut down with soreness in the back of his right elbow. The 33-year-old would like to throw a live batting practice before he restarts his minor-league rehab assignment.
Happ took another step in a positive direction. He originally suffered a nasty head injury in his last start May 7 against Tampa Bay but is having more trouble with a knee injury as a result of the subsequent fall.
Schafer came into play Tuesday batting .231 (3 for 13) with two RBI and five strikeouts in 12 June games (one start).